This invention relates to build-up cladding of a copper alloy for forming a valve seat in an engine cylinder head.
A method of forming a valve seat for an engine intake valve or exhaust valve is known wherein copper. alloy powder is dissolved by a laser beam and accumulated on a cylinder head base metal along a rim of an intake port or exhaust port.
As an example of such a powdered copper alloy, Tokkai Hei 8-35027 published by the Japanese Patent Office in 1996 discloses a powder material comprising 10-30 wt % nickel (Ni), 0.5-5.0 wt % silicon (Si), and 2.0-15.0 wt % of at least one of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This powder material may also comprise 2.0-15.0 wt % iron (Fe) or 1.0-10.0 wt % chromium (Cr). It may also comprise 0.01-0.1% misch metal or 0.1-1.0 wt % phosphorus (P), 1.0-10.0 wt % manganese (Mn) and 0.5-3.0 wt % boron (B). The remaining components are copper (Cu) and impurities.
According to tests performed by the inventors, a valve seat formed using this powder material displayed superior in abrasion resistance, but microcracks occurred sporadically in the valve seat after cladding.
It is therefore an object of this invention to provide an abrasion resistant copper alloy in which microcracks rarely form.
It is a further object of this invention to improve the quality of an engine valve seat.
In order to achieve the above objects, this invention provides an abrasion resistant copper alloy consisting of copper (Cu). 6-9 wt % nickel (Ni), 1-5 wt % silicon (Si), and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu). 6-9 wt % nickel (Ni), 1-5 wt % silicon (Si), 0.5-1.5 wt % iron (Fe), and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu). 6-9 wt % nickel (Ni), 1-5 wt % silicon (Si), 0.5-1.5 wt % iron (Fe), 1-5 wt % chromium (Cr), and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu). 6-9 wt % nickel (Ni), 1-5 wt % silicon (Si), 1-5 wt % chromium (Cr), 0.5-0.9 wt % aluminum (Al), and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu), 6-9 wt % nickel (Ni), 1-5 wt % silicon (Si), 0.5-1.5 wt % iron (Fe), 0.5-0.9 wt % aluminum (Al), 5-15 wt % cobalt (Co), and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu), 6-9 wt % nickel (Ni), 1-5 wt % silicon (Si), 0.5-1.5 wt % iron (Fe), 0.1-1.0 wt % phosphorus (P), and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu), 6-9 wt % nickel (Ni), 1-5 wt % silicon (Si), 0.5-1.5 wt % iron (Fe), 1-5 wt % chromium (Cr), 0.1-1.0 wt % phosphorus (P), 1-10 wt % manganese (Mn), and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu), 6-9 wt % nickel (Ni), 1-5 wt % silicon (Si), 0.5-1.5 wt % iron (Fe), 1-5 wt % chromium (Cr), 0.5-0.9 wt % aluminum (Al), 0.1-1.0 wt % phosphorus (P), 1-10 wt % manganese (Mn), 0.01-0.1 wt % rare earth metal, and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu), 9-15 wt % nickel (Ni), 1-5 wt % silicon (Si), 0.5-1.5 wt % iron (Fe), 1-5 wt % chromium (Cr), 0.5-0.9 wt % aluminum (Al), 0.1-1.0 wt % phosphorus (P), and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu), 9-15 wt % nickel (Ni), 1-5 wt % silicon (Si), 0.5-1.5 wt % iron (Fe), 1-5 wt % chromium (Cr), 0.5-0.9 wt % aluminum (Al), 0.1-1.0 wt % phosphorus (P), 1-10 wt % manganese (Mn), and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
This invention also provides an abrasion resistant copper alloy consisting of copper (Cu), 9-15 wt % nickel (Ni), 1-5 wt % silicon (Si), 0.5-1.5 wt % iron (Fe), 1-5 wt % chromium (Cr), 0.5-0.9 wt % aluminum (Al), 0.1-1.0 wt % phosphorus (P), 1-10 wt % manganese (Mn), 0.01-0.1 wt % rare earth metal, and 1-5 wt % of a material selected from the group consisting of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V).
The above copper alloys are preferably provided in the form of powder for build-up cladding using a laser beam.
Such build-up cladding is preferably used for forming a valve seat of intake and exhaust valves arranged in an engine cylinder head.
The details as well as other features and advantages of this invention are set forth in the remainder of the specification and are shown in the accompanying drawings.